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It has a tev valve. And yes iv cleaned the condenser. It's a older unit. It's been retrofitted to r404. And I forgot to mention it has a lot of bubbles in the sight glass. Almost looks like the refrigerant is boiling. There that much bubbles. Thanks for your reply.

Where is your high side gauge manifold hose connected, liquid line, discharge line?

If you have a restriction upstream from the sight glass, it will flash.

Possible you have a restriction - plugged drier or other restriction. If it was retrofitted to 404a, the oil may have been changed to polyol ester. Polyol ester oil acts like a detergent, so if there was any crap in the system it will loosen it up and plug driers and cause other problems. Could be non-condensables as well.

Is there a noticeable temperature drop across the drier right now?

I think you're on par, pull charge, change drier, blow out system with nitrogen to ensure no other restrictions. Pull a good vacuum and weigh in the correct charge (if applicable).

What is the control set for? If it's set for 380, it's set too low. I'm also not understanding how you are determining what the pressures "should" be, unless you are familiar with this unit and if that's the case, how did the non condensables get inside? Also, the SH being 20* too high. Where are you checking your SH at? If it's not at the coil, it doesn't really matter as there are a number of other reasons the SH at the pump could be high. Does the unit have a headmaster?

Officially, Down for the count

YOU HAVE TO GET OFF YOUR ASS TO GET ON YOUR FEET

I know enough to know, I don't know enoughLiberalism-Ideas so good they mandate them

I have a reachin produce cooler that is shutting down. The high pressure control is shutting the compressor down. Here are the symptoms. The cooler is a r404 unit. It was 95 dg. Ambient.

High head pressure, should be 330 but was reading 380
High low pressure, should be 50 but was reading 68
High superheat, it was 20 dg to high
Low sub cooling, about 2 dg low.

You aren't getting rid of the heat. Airflow, dirty coil. No restriction since the subcooling isn't high. No air in the system for the same reason.
Post actual temps. Gives a better picture.
Out of curiosity. What are you looking for, for subcooling and superheat? Where are you measuring both?

If you suspect non condensables, pump the unit down......if you can....if you can't pump down then shut the king valve and then shut off the unit. Disconnect the compressor and allow the condenser fan to run for half an hour. Measure your ambient temp and check it against your hi side pressure. If they don't match you have crap gas.